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</style>
</head>
<body class='typora-export' oncopy="return false" oncut="return false" onpaste="return false">
<div  id='write'  class = 'is-mac'><h1><a name='header-c967' class='md-header-anchor '></a>数据库实验报告</h1><h2><a name='header-c1302' class='md-header-anchor '></a>创建数据表</h2><h3><a name='header-c969' class='md-header-anchor '></a>创建Sailors表</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">CREATE</span> <span class="cm-keyword">TABLE</span> Sailors (</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  sid <span class="cm-builtin">char</span>(<span class="cm-number">10</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  sname <span class="cm-builtin">char</span>(<span class="cm-number">20</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  rating <span class="cm-builtin">int</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  age <span class="cm-builtin">int</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  PRIMARY KEY (sid)</span></pre><pre class=""><span style="padding-right: 0.1px;">);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 182px;"></div></div></div></pre><h3><a name='header-c971' class='md-header-anchor '></a>创建Boats表</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap "><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">CREATE</span> <span class="cm-keyword">TABLE</span> Boats (</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  bid <span class="cm-builtin">char</span>(<span class="cm-number">10</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  bname <span class="cm-builtin">char</span>(<span class="cm-number">20</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  color <span class="cm-builtin">char</span>(<span class="cm-number">10</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  PRIMARY KEY (bid)</span></pre><pre class=""><span style="padding-right: 0.1px;">);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 156px;"></div></div></div></pre><h3><a name='header-c973' class='md-header-anchor '></a>创建Reserves表</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">CREATE</span> <span class="cm-keyword">TABLE</span> Reserves (</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  sid <span class="cm-builtin">char</span>(<span class="cm-number">10</span>) REFERENCES Sailors (sid) <span class="cm-keyword">ON</span> <span class="cm-keyword">DELETE</span> CASCADE,</span></pre><pre class=""><span style="padding-right: 0.1px;">  bid <span class="cm-builtin">char</span>(<span class="cm-number">10</span>) REFERENCES Boats (bid) <span class="cm-keyword">ON</span> <span class="cm-keyword">DELETE</span> CASCADE,</span></pre><pre class=""><span style="padding-right: 0.1px;">  rdate <span class="cm-builtin">date</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  PRIMARY KEY (sid, bid, rdate)</span></pre><pre class=""><span style="padding-right: 0.1px;">);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 156px;"></div></div></div></pre><h2><a name='header-c975' class='md-header-anchor '></a>插入数据</h2><h3><a name='header-c976' class='md-header-anchor '></a>向Sailors表插入数据</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'dustin'</span>, <span class="cm-number">7</span>, <span class="cm-number">45</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'29'</span>, <span class="cm-string">'brustus'</span>, <span class="cm-number">1</span>, <span class="cm-number">33</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'31'</span>, <span class="cm-string">'lubber'</span>, <span class="cm-number">8</span>, <span class="cm-number">56</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'32'</span>, <span class="cm-string">'andy'</span>, <span class="cm-number">8</span>, <span class="cm-number">26</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'58'</span>, <span class="cm-string">'rusty'</span>, <span class="cm-number">10</span>, <span class="cm-number">35</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'64'</span>, <span class="cm-string">'horatio'</span>, <span class="cm-number">7</span>, <span class="cm-number">35</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'71'</span>, <span class="cm-string">'zorba'</span>, <span class="cm-number">10</span>, <span class="cm-number">35</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'74'</span>, <span class="cm-string">'horatio'</span>, <span class="cm-number">9</span>, <span class="cm-number">35</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'85'</span>, <span class="cm-string">'art'</span>, <span class="cm-number">3</span>, <span class="cm-number">26</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'86'</span>, <span class="cm-string">'john'</span>, <span class="cm-number">1</span>, <span class="cm-number">17</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'95'</span>, <span class="cm-string">'bob'</span>, <span class="cm-number">3</span>, <span class="cm-number">64</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'96'</span>, <span class="cm-string">'frodo'</span>, <span class="cm-number">3</span>, <span class="cm-number">26</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'98'</span>, <span class="cm-string">'tom'</span>, <span class="cm-number">3</span>, <span class="cm-number">17</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 676px;"></div></div></div></pre><p>插入完成后Sailors表内容如下</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 22         | dustin               |      7 |  45
 29         | brustus              |      1 |  33
 31         | lubber               |      8 |  56
 32         | andy                 |      8 |  26
 58         | rusty                |     10 |  35
 64         | horatio              |      7 |  35
 71         | zorba                |     10 |  35
 74         | horatio              |      9 |  35
 85         | art                  |      3 |  26
 86         | john                 |      1 |  17
 95         | bob                  |      3 |  64
 96         | frodo                |      3 |  26
 98         | tom                  |      3 |  17
(13 rows)</pre><h3><a name='header-c981' class='md-header-anchor '></a>向Boats表插入数据</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'101'</span>, <span class="cm-string">'A'</span>, <span class="cm-string">'red'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'102'</span>, <span class="cm-string">'B'</span>, <span class="cm-string">'green'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'103'</span>, <span class="cm-string">'C'</span>, <span class="cm-string">'blue'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'104'</span>, <span class="cm-string">'D'</span>, <span class="cm-string">'white'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'105'</span>, <span class="cm-string">'E'</span>, <span class="cm-string">'red'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'106'</span>, <span class="cm-string">'F'</span>, <span class="cm-string">'blue'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'107'</span>, <span class="cm-string">'G'</span>, <span class="cm-string">'green'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 364px;"></div></div></div></pre><p>插入完成后Boats表内容如下</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    bid     |        bname         |   color    
------------+----------------------+------------
 101        | A                    | red       
 102        | B                    | green     
 103        | C                    | blue      
 104        | D                    | white     
 105        | E                    | red       
 106        | F                    | blue      
 107        | G                    | green     
(7 rows)</pre><h3><a name='header-c986' class='md-header-anchor '></a>向Reserves表插入数据</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'101'</span>, <span class="cm-string">'2010-01-08'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'102'</span>, <span class="cm-string">'2010-01-09'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'29'</span>, <span class="cm-string">'103'</span>, <span class="cm-string">'2010-01-09'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'31'</span>, <span class="cm-string">'102'</span>, <span class="cm-string">'2010-02-11'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'104'</span>, <span class="cm-string">'2010-03-08'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'103'</span>, <span class="cm-string">'2010-03-10'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'32'</span>, <span class="cm-string">'105'</span>, <span class="cm-string">'2010-03-11'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'32'</span>, <span class="cm-string">'106'</span>, <span class="cm-string">'2010-03-18'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'32'</span>, <span class="cm-string">'102'</span>, <span class="cm-string">'2010-03-19'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'58'</span>, <span class="cm-string">'104'</span>, <span class="cm-string">'2010-03-20'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'64'</span>, <span class="cm-string">'105'</span>, <span class="cm-string">'2010-03-20'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'95'</span>, <span class="cm-string">'101'</span>, <span class="cm-string">'2010-04-02'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'85'</span>, <span class="cm-string">'102'</span>, <span class="cm-string">'2010-04-05'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'101'</span>, <span class="cm-string">'2010-04-07'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'105'</span>, <span class="cm-string">'2010-05-01'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'106'</span>, <span class="cm-string">'2010-06-18'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'22'</span>, <span class="cm-string">'107'</span>, <span class="cm-string">'2010-07-09'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'31'</span>, <span class="cm-string">'106'</span>, <span class="cm-string">'2010-08-06'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'32'</span>, <span class="cm-string">'105'</span>, <span class="cm-string">'2010-08-06'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'29'</span>, <span class="cm-string">'104'</span>, <span class="cm-string">'2010-08-07'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'64'</span>, <span class="cm-string">'103'</span>, <span class="cm-string">'2010-09-05'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'58'</span>, <span class="cm-string">'102'</span>, <span class="cm-string">'2010-09-09'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'64'</span>, <span class="cm-string">'104'</span>, <span class="cm-string">'2010-11-03'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'64'</span>, <span class="cm-string">'105'</span>, <span class="cm-string">'2010-11-04'</span>);</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'31'</span>, <span class="cm-string">'106'</span>, <span class="cm-string">'2010-12-06'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 1300px;"></div></div></div></pre><p>插入完成后Reserves表内容如下</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |    bid     |   rdate    
------------+------------+------------
 22         | 101        | 2010-01-08
 22         | 102        | 2010-01-09
 29         | 103        | 2010-01-09
 31         | 102        | 2010-02-11
 22         | 104        | 2010-03-08
 22         | 103        | 2010-03-10
 32         | 105        | 2010-03-11
 32         | 106        | 2010-03-18
 32         | 102        | 2010-03-19
 58         | 104        | 2010-03-20
 64         | 105        | 2010-03-20
 95         | 101        | 2010-04-02
 85         | 102        | 2010-04-05
 22         | 101        | 2010-04-07
 22         | 105        | 2010-05-01
 22         | 106        | 2010-06-18
 22         | 107        | 2010-07-09
 31         | 106        | 2010-08-06
 32         | 105        | 2010-08-06
 29         | 104        | 2010-08-07
 64         | 103        | 2010-09-05
 58         | 102        | 2010-09-09
 64         | 104        | 2010-11-03
 64         | 105        | 2010-11-04
 31         | 106        | 2010-12-06
(25 rows)</pre><h2><a name='header-c991' class='md-header-anchor '></a>SQL操作</h2><h3><a name='header-c992' class='md-header-anchor '></a>查找订了103号船的水手</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  *</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> bid = <span class="cm-string">'103'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 182px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 22         | dustin               |      7 |  45
 29         | brustus              |      1 |  33
 64         | horatio              |      7 |  35
(3 rows)</pre><h3><a name='header-c997' class='md-header-anchor '></a>查找订了红色船水手的姓名</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  sname</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> bid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  bid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> color = <span class="cm-string">'red'</span>));</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 260px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>        sname         
----------------------
 andy                
 dustin              
 bob                 
 horatio             
(4 rows)</pre><h3><a name='header-c1002' class='md-header-anchor '></a>将年龄小于30的水手级别加1</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">UPDATE</span> Sailors</span></pre></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SET</span> rating = rating + <span class="cm-number">1</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> age &lt; <span class="cm-number">30</span>;</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 78px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>UPDATE 5</pre><p>Sailors表更新后内容如下</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 22         | dustin               |      7 |  45
 29         | brustus              |      1 |  33
 31         | lubber               |      8 |  56
 58         | rusty                |     10 |  35
 64         | horatio              |      7 |  35
 71         | zorba                |     10 |  35
 74         | horatio              |      9 |  35
 95         | bob                  |      3 |  64
 32         | andy                 |      9 |  26
 85         | art                  |      4 |  26
 86         | john                 |      2 |  17
 96         | frodo                |      4 |  26
 98         | tom                  |      4 |  17
(13 rows)</pre><h3><a name='header-c1010' class='md-header-anchor '></a>查找订了红色船而没有定绿色船的水手姓名</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  sname</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> bid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  bid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> color = <span class="cm-string">'red'</span>))</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">AND</span> sid <span class="cm-keyword">NOT</span> <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> bid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  bid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> color = <span class="cm-string">'green'</span>));</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 442px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>        sname         
----------------------
 horatio             
 bob                 
(2 rows)</pre><h3><a name='header-c1015' class='md-header-anchor '></a>查找没有定过船的水手信息</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  *</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">NOT</span> <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 156px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 71         | zorba                |     10 |  35
 74         | horatio              |      9 |  35
 86         | john                 |      2 |  17
 96         | frodo                |      4 |  26
 98         | tom                  |      4 |  17
(5 rows)</pre><h3><a name='header-c1020' class='md-header-anchor '></a>查找订过船而没有订过红色船的水手信息</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  *</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves)</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">AND</span> sid <span class="cm-keyword">NOT</span> <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> bid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  bid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> color = <span class="cm-string">'red'</span>));</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 338px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 29         | brustus              |      1 |  33
 31         | lubber               |      8 |  56
 58         | rusty                |     10 |  35
 85         | art                  |      4 |  26
(4 rows)</pre><h3><a name='header-c1025' class='md-header-anchor '></a>查找没有定过红色船的水手信息</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  *</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">NOT</span> <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> bid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  bid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Boats</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> color = <span class="cm-string">'red'</span>));</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 260px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 29         | brustus              |      1 |  33
 31         | lubber               |      8 |  56
 58         | rusty                |     10 |  35
 71         | zorba                |     10 |  35
 74         | horatio              |      9 |  35
 85         | art                  |      4 |  26
 86         | john                 |      2 |  17
 96         | frodo                |      4 |  26
 98         | tom                  |      4 |  17
(9 rows)</pre><h3><a name='header-c1030' class='md-header-anchor '></a>查找定过所有船的水手姓名和编号</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  S2<span class="cm-variable-2">.sname</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  S2<span class="cm-variable-2">.sid</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S2</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> S2<span class="cm-variable-2">.sid</span> <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.sid</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">COUNT</span>(<span class="cm-keyword">DISTINCT</span> bid),</span></pre><pre class=""><span style="padding-right: 0.1px;">  sid</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves</span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> sid) S</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> S<span class="cm-variable-2">.count</span> <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">COUNT</span>(bid)</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Boats));</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 364px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>        sname         |    sid     
----------------------+------------
 dustin               | 22        
(1 row)</pre><h3><a name='header-c1035' class='md-header-anchor '></a>查找年龄最大的水手姓名和年龄</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.sname</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.age</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> S<span class="cm-variable-2">.age</span> = (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  MAX(S2<span class="cm-variable-2">.age</span>)</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S2);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 182px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>        sname         | age 
----------------------+-----
 bob                  |  64
(1 row)</pre><h3><a name='header-c1040' class='md-header-anchor '></a>统计水手表中每个级别组的平均年龄和级别组</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  AVG(age),</span></pre><pre class=""><span style="padding-right: 0.1px;">  rating</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> rating;</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 130px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>         avg         | rating 
---------------------+--------
 56.0000000000000000 |      8
 23.0000000000000000 |      4
 33.0000000000000000 |      1
 64.0000000000000000 |      3
 35.0000000000000000 |     10
 30.5000000000000000 |      9
 17.0000000000000000 |      2
 40.0000000000000000 |      7
(8 rows)</pre><h3><a name='header-c1045' class='md-header-anchor '></a>统计水手表中每个人数不少于2人的级别组中年满18岁水手的平均年龄和级别组</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  AVG(S<span class="cm-variable-2">.age</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.rating</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> S<span class="cm-variable-2">.age</span> &gt;= <span class="cm-number">18</span></span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> S<span class="cm-variable-2">.rating</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">HAVING</span> <span class="cm-keyword">COUNT</span>(*) &gt;= <span class="cm-number">2</span>;</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 182px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>         avg         | rating 
---------------------+--------
 26.0000000000000000 |      4
 35.0000000000000000 |     10
 30.5000000000000000 |      9
 40.0000000000000000 |      7
(4 rows)</pre><h3><a name='header-c1050' class='md-header-anchor '></a>统计水手表中每个级别组的人数</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">COUNT</span>(sid),</span></pre><pre class=""><span style="padding-right: 0.1px;">  rating</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> rating;</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 130px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'> count | rating 
-------+--------
     1 |      8
     3 |      4
     1 |      1
     1 |      3
     2 |     10
     2 |      9
     1 |      2
     2 |      7
(8 rows)</pre><h3><a name='header-c1055' class='md-header-anchor '></a>统计水手表中人数最少的级别组及人数</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  R<span class="cm-variable-2">.count</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  R<span class="cm-variable-2">.rating</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">COUNT</span>(S<span class="cm-variable-2">.sid</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.rating</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S</span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> S<span class="cm-variable-2">.rating</span>) R</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> R<span class="cm-variable-2">.count</span> = (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  MIN(R2<span class="cm-variable-2">.count</span>)</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">COUNT</span>(S<span class="cm-variable-2">.sid</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.rating</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S</span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> S<span class="cm-variable-2">.rating</span>) R2);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 390px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'> count | rating 
-------+--------
     1 |      8
     1 |      1
     1 |      3
     1 |      2
(4 rows)</pre><h3><a name='header-c1060' class='md-header-anchor '></a>查找定过船而没有定过相同的船的水手姓名</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  S<span class="cm-variable-2">.sname</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors S</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> EXISTS (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  R2<span class="cm-variable-2">.sid</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">COUNT</span>(*) boatcount,</span></pre><pre class=""><span style="padding-right: 0.1px;">  R<span class="cm-variable-2">.sid</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;">  B<span class="cm-variable-2">.bid</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Reserves R,</span></pre><pre class=""><span style="padding-right: 0.1px;"> &nbsp; &nbsp; Boats B</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> R<span class="cm-variable-2">.bid</span> = B<span class="cm-variable-2">.bid</span></span></pre><pre class=""><span style="padding-right: 0.1px;">GROUP <span class="cm-keyword">BY</span> R<span class="cm-variable-2">.sid</span>,</span></pre><pre class=""><span style="padding-right: 0.1px;"> &nbsp; &nbsp; &nbsp; &nbsp; B<span class="cm-variable-2">.bid</span>) R2</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> R2<span class="cm-variable-2">.boatcount</span> = <span class="cm-number">1</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">AND</span> R2<span class="cm-variable-2">.sid</span> = S<span class="cm-variable-2">.sid</span>)</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 416px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>        sname         
----------------------
 dustin              
 brustus             
 lubber              
 rusty               
 horatio             
 bob                 
 andy                
 art                 
(8 rows)</pre><h3><a name='header-c1065' class='md-header-anchor '></a>删除名字叫lubber的水手的定船信息</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">DELETE</span> <span class="cm-keyword">FROM</span> Reserves</span></pre></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> sid <span class="cm-keyword">IN</span> (<span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;"> &nbsp;  sid</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">WHERE</span> sname = <span class="cm-string">'lubber'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 130px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>DELETE 3</pre><p>Reserves表删除指定信息后内容如下</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |    bid     |   rdate    
------------+------------+------------
 22         | 101        | 2010-01-08
 22         | 102        | 2010-01-09
 29         | 103        | 2010-01-09
 22         | 104        | 2010-03-08
 22         | 103        | 2010-03-10
 32         | 105        | 2010-03-11
 32         | 106        | 2010-03-18
 32         | 102        | 2010-03-19
 58         | 104        | 2010-03-20
 64         | 105        | 2010-03-20
 95         | 101        | 2010-04-02
 85         | 102        | 2010-04-05
 22         | 101        | 2010-04-07
 22         | 105        | 2010-05-01
 22         | 106        | 2010-06-18
 22         | 107        | 2010-07-09
 32         | 105        | 2010-08-06
 29         | 104        | 2010-08-07
 64         | 103        | 2010-09-05
 58         | 102        | 2010-09-09
 64         | 104        | 2010-11-03
 64         | 105        | 2010-11-04
(22 rows)</pre><h3><a name='header-c1073' class='md-header-anchor '></a>创建一个级别小于6的水手视图</h3><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">CREATE</span> VIEW Level_less_than_six</span></pre></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">AS</span></span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre><pre class=""><span style="padding-right: 0.1px;">  *</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Sailors</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">WHERE</span> rating &lt; <span class="cm-number">6</span>;</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 156px;"></div></div></div></pre><p>目前该视图内容如下</p><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">SELECT</span></span></pre></div><pre class=""><span style="padding-right: 0.1px;">  *</span></pre><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">FROM</span> Level_less_than_six;</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 78px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>    sid     |        sname         | rating | age 
------------+----------------------+--------+-----
 29         | brustus              |      1 |  33
 95         | bob                  |      3 |  64
 85         | art                  |      4 |  26
 86         | john                 |      2 |  17
 96         | frodo                |      4 |  26
 98         | tom                  |      4 |  17
(6 rows)</pre><h3><a name='header-c1081' class='md-header-anchor '></a>Students表的建立与插入</h3><h4><a name='header-c1082' class='md-header-anchor '></a>建立Students表</h4><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code" style=""><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">CREATE</span> <span class="cm-keyword">TABLE</span> Students (</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  sid <span class="cm-builtin">char</span>(<span class="cm-number">3</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  sname <span class="cm-builtin">char</span>(<span class="cm-number">8</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  age <span class="cm-builtin">int</span> CHECK (age &gt;= <span class="cm-number">15</span> <span class="cm-keyword">AND</span> age &lt;= <span class="cm-number">40</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  grade <span class="cm-builtin">char</span>(<span class="cm-number">4</span>),</span></pre><pre class=""><span style="padding-right: 0.1px;">  PRIMARY KEY (sid)</span></pre><pre class=""><span style="padding-right: 0.1px;">);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 182px;"></div></div></div></pre><h4><a name='header-c1084' class='md-header-anchor '></a>数据插入实验</h4><h5><a name='header-c1085' class='md-header-anchor '></a>第一次插入</h5><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Students</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'001'</span>, <span class="cm-string">'abc'</span>, <span class="cm-number">18</span>, <span class="cm-string">'2001'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 52px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>INSERT 0 1</pre><p>此时Students表内容</p><pre class='md-fences mock-cm' style='display:block;position:relative'> sid |  sname   | age | grade 
-----+----------+-----+-------
 001 | abc      |  18 | 2001
(1 row)</pre><h5><a name='header-c1093' class='md-header-anchor '></a>第二次插入</h5><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap " lang="sql"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Students</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'002'</span>, <span class="cm-string">'bcd'</span>, <span class="cm-number">19</span>, <span class="cm-string">'2002'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 52px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>INSERT 0 1</pre><p>此时Students表内容</p><pre class='md-fences mock-cm' style='display:block;position:relative'> sid |  sname   | age | grade 
-----+----------+-----+-------
 001 | abc      |  18 | 2001
 002 | bcd      |  19 | 2002
(2 rows)</pre><h5><a name='header-c1126' class='md-header-anchor '></a>第三次插入</h5><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap " lang="sql"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Students</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'003'</span>, <span class="cm-string">'def'</span>, <span class="cm-number">13</span>, <span class="cm-string">'2004'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 52px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>ERROR:  new row for relation &quot;students&quot; violates check constraint &quot;students_age_check&quot;
DETAIL:  Failing row contains (003, def     , 13, 2004).</pre><p>此时Students表内容</p><pre class='md-fences mock-cm' style='display:block;position:relative'> sid |  sname   | age | grade 
-----+----------+-----+-------
 001 | abc      |  18 | 2001
 002 | bcd      |  19 | 2002
(2 rows)</pre><h5><a name='header-c1158' class='md-header-anchor '></a>第四次插入</h5><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap  " lang="sql"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Students</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'004'</span>, <span class="cm-string">'kdz'</span>, <span class="cm-number">19</span>, <span class="cm-string">'2007'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 52px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>INSERT 0 1</pre><p>此时Students表内容</p><pre class='md-fences mock-cm' style='display:block;position:relative'> sid |  sname   | age | grade 
-----+----------+-----+-------
 001 | abc      |  18 | 2001
 002 | bcd      |  19 | 2002
 004 | kdz      |  19 | 2007
(3 rows)</pre><h5><a name='header-c1190' class='md-header-anchor '></a>第五次插入</h5><pre class="md-fences md-end-block" lang="sql"> <div class="CodeMirror cm-s-inner CodeMirror-wrap   " lang="sql"><div style="overflow: hidden; position: relative; width: 3px; height: 0px; top: 0px; left: 4px;"></div><div class="CodeMirror-hscrollbar" style="left: 0px;"><div style="height: 100%; min-height: 1px; width: 0px;"></div></div><div class="CodeMirror-vscrollbar"><div style="min-width: 1px; height: 0px;"></div></div><div class="CodeMirror-scrollbar-filler"></div><div class="CodeMirror-gutter-filler"></div><div class="CodeMirror-scroll" tabindex="-1"><div class="CodeMirror-sizer" style="margin-left: 0px; min-height: 0px;"><div style="position: relative; top: 0px;"><div class="CodeMirror-lines"><div style="position: relative; outline: none;"><div class="CodeMirror-measure"><pre><span>xxxxxxxxxx</span></pre></div><div class="CodeMirror-measure"></div><div style="position: relative; z-index: 1;"></div><div class="CodeMirror-code"><div class="CodeMirror-activeline" style="position: relative;"><div class="CodeMirror-activeline-background CodeMirror-linebackground"></div><pre class=""><span style="padding-right: 0.1px;"><span class="cm-keyword">INSERT</span> <span class="cm-keyword">INTO</span> Students</span></pre></div><pre class=""><span style="padding-right: 0.1px;">  <span class="cm-keyword">VALUES</span> (<span class="cm-string">'005'</span>, <span class="cm-string">'ddd'</span>, <span class="cm-number">47</span>, <span class="cm-string">'2008'</span>);</span></pre></div></div></div></div></div><div style="position: absolute; height: 30px; width: 1px; top: 0px;"></div><div class="CodeMirror-gutters" style="display: none; height: 52px;"></div></div></div></pre><p>结果</p><pre class='md-fences mock-cm' style='display:block;position:relative'>ERROR:  new row for relation &quot;students&quot; violates check constraint &quot;students_age_check&quot;
DETAIL:  Failing row contains (005, ddd     , 47, 2008).</pre><p>此时Students表内容</p><pre class='md-fences mock-cm' style='display:block;position:relative'> sid |  sname   | age | grade 
-----+----------+-----+-------
 001 | abc      |  18 | 2001
 002 | bcd      |  19 | 2002
 004 | kdz      |  19 | 2007
(3 rows)</pre><h2><a name='header-c1222' class='md-header-anchor '></a>LICENSE</h2><pre class='md-fences mock-cm' style='display:block;position:relative'>MIT License

Copyright (c) 2017 LI GEN LING

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the &quot;Software&quot;), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED &quot;AS IS&quot;, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.</pre><p></p></div>
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